Now here the Login Url will be the endpoint url for your SFDC server and the Customer Key and Customer secret is provided by the connected app in SFDC that points to your AEM server.
Once you click on connect to salesforce then your AEM server is now connected to salesforce to submit the leads.
Now as next step we need to utilize the workflow that we had initially to send the leads. Let's consider a node at /tmp/sfdc/myuser in AEM which will have below properties and all these and we will pass this node path as the payload in the Salesforce.com Export workflow.
Once you trigger the workflow then the leads will be created in the SFDC server.